The present invention relates generally to methods and materials for detection of N. gonorrhoeae in a microbial growth culture and more specifically relates to a rapid and reproducible reverse passive hemagglutination (RPHA) test for any of the known strains of the organisms.
Presently available procedures for identification of N. gonorrhoeae in a culture medium, e.g., Thayer-Martin agar, involve preliminary screening on the basis of source, morphology, gram stain and oxidase testing. Oxidase-positive gram-negative diplococci exhibiting typical colonial morphology on Thayer-Martin medium seeded from the genitourinary tract of a patient are considered presumptively gonococci. Confirmation of this preliminary determination conventionally involves examination of the organism within the framework of additional test schemes specifically directed to the detection of N. gonorrhoeae as opposed to other organisms displaying similar characteristics. Such specific tests include carbohydrate degradation screening which requires approximately 48 hours to complete and is sometimes unreliable owing to the fact that some strains of N. gonorrhoeae may either fail to grow or may give false negative sugar reactions. An alternative commercial screening procedure involves the use of fluorescent antibodies and, while the procedure is relatively rapid and specific for all N. gonorrhoeae strains, the use of a rather expensive fluorescence microscope by a highly skilled technician is required for the determination. See, e.g., Health Laboratory Science, Vol. 12, No. 3, pp. 215-218 ( 1975).
While it was generally known that RPHA testing for confirmation of microorganisms is faster and more reproducible than, e.g., carbohydrate degradation analysis, such procedures have been believed to be inappropriate to screening for N. gonorrhoeae owing to the frequently acute specificity of antibodies to the different strains of N. gonorrhoeae. It was generally thought, for example, that a great number of assays involving a similarly large number of specific antibodies might be necessary to dispositively characterize an organism as one of the many N. gonorrhoeae strains.
The art, therefore, presently has a need for a rapid, reproducible method for identification of the presence of N. gonorrhoeae which does not involve the tedious or expensive procedures of conventional methods.